This article was created for the Beta version of Georeferencer, there is a more recent guide here.

Contents

What is OxTS Georeferencer?
Where to get it?
Workflow guide

What is OxTS Georeferencer?

OxTS Georeferencer is a tool developed by OxTS to combine INS trajectory data with raw LiDAR data to create a georeferenced 3D Pointcloud. It takes a PCAP file collected with a Velodyne VLP-16 LiDAR scanner (synchronised in real-time with an OxTS inertial navigation system (INS)), a processed NCOM file from the OxTS INS, and some required configuration files, to create a LAS pointcloud file that can be viewed in many 3rd party LiDAR software packages.

For help integrating a Velodyne VLP-16 with an OxTS INS, see our guide here!

Please note: OxTS Georeferencer is still in beta. The georeferencing and pointcloud creation side of OxTS Georeferencer is available as a beta on request. The boresight calibration side is not currently available externally.

Where to get it?

If you would like to download some example LAS files and screenshots created with OxTS Georeferencer, you can access them here:

https://oxts.box.com/v/geocloudexampleLAS

If you would like to try out the OxTS Georeferencer [BETA] tool and help us develop it further, please contact us here for an invite to download the software. The software is currently a portable version and does not include an installer, but it does include a README and video run through of the workflow. Please note this download does not include the boresight calibration capability.

Workflow overview

The system diagram below shows the steps required to create your LAS file. For full details on the process, contact us here.

NOTES:

• The VAT file can be found in the ExtractedConfiguration folder created when processing the RD file with OxTS NAVsolve.
• The LIP and LIR files define the linear displacement and boresight alignment of the INS-LiDAR system. They can be created and prepared in advance using a simple text editor.
• Running OxTSgeoreferencer.exe from the command line will produce a fully georeferenced 3D pointcloud in the LAS format, which can then be dropped into many 3rd party applications for further processing and analysis. There are also a number of free, simple LAS viewers available such as CloudCompare or QT reader.

Boresight alignment

• The LIP file should contain 3 lines with a number on each describing the x, y, and z offsets from the INS to LiDAR measurements points in the INS frame. The measurements should be made as accurate as possible, within 1 cm.
• The LIR file can be created by performing a boresight alignment calibration. If boresight values are already known they should be entered into this file. It should contain 3 lines with a number on each describing the heading, pitch, and roll offsets from the INS to the LiDAR. If performing a calibration, the initial measurements do not need to be accurate as the alignment converges regardless of the initial inputs.